Button sewing machine

ABSTRACT

The invention concerns a sewing machine capable, in one operational cycle, of loosely sewing on by blind stitching of a button to a workpiece and winding threads around the thus formed post. A program member driven by the main drive shaft controls a button clamping and turning device, the sewing mechanism proper, the reciprocation of a work-supporting plate and a work-gripping device which is positively coupled to the button turning shaft in the direction of work movement but which is independent thereof in other directions.

nite States atent [191 Kovacs et a1.

[ BU'I'ION SEWING MACHINE [75] Inventors: Jozsef Kovacs; Janos Hegyesi;

Agoston Sarlos, all of Budapest, Hungary [73] Assignee: Csepeli Kerekpar-Es Varrogepgyar,

Budapest-Csepel, Hungary [22] Filed: Sept. 24, 1971 [21] Appl. No.: 183,380

[30] Foreign Application Priority Data Oct. 22, 1970 Hungary ..790/70 [52] US. Cl. 112/110 [51] lint. Cl D05b 3/14 [58] Field of Search 112/108114, 1 12/104 [56] References Cited UNITED STATES PATENTS 3,509,838 5/1970 Bowin 112/110 3,680,506 8/1972 Hager et a1. 112/112 [451 Apr. 30, 1974 2,645,192 7/1953 McCann 112/110 3,125,046 3/1964 Pedersen 112/110 3,132,613 5/1964 Johnson et al.... 112/110 3,182,618 5/1965 Pedersen 112/110 3,246,618 4/1966 Johnson 1 12/1 10 3,361,097 l/1968 Pederson et al. 112/110 3,440,984 4/1969 Hote 112/110 Primary Examiner-Geo. V. Larkin [57 ABSTRACT The invention concerns a sewing machine capable, in one operational cycle, of loosely sewing on by blind stitching of a button to a workpiece and winding threads around the thus formed post. A program member driven by the main drive shaft controls a button clamping and turning device, the sewing mechanism proper, the reciprocation of a work-Supporting plate and a work-gripping device which is positively coupled to the button turning shaft in the direction of work movement but which is independent thereof in other directions.

6 Claims, 3 Drawing Figures PAT mmso m4 SHEET 1 OF 3 INVENTORS; JOZSEF KOVAcS JANos HEGYESI AGOSTON SARLOS ATTORNEY YTEmPso we BLOWN sum 2 or s BUTTON SEWING MACHINE The invention concerns a combined button sewing and post winding machine for the achievement, during one working cycle of the machine, of loosely sewing on a button with blind stitching and winding thread around the post formed by loose threads. It is known that in the gannent industry post-wound button sewing is employed for medium to heavy goods (e.g., jackets, winter overcoats). First, a button is sewn on so that during sewing a gap is formed, e.g., with a spacer plate, between the work or fabric and the button. The threads running between the loosely sewn button and the work, called post or stem" then have threads wrapped or wound round them. In the readyto-wear garment industry the sewing of buttons is performed with per se known button sewing machines, while the post winding is performed with similarly per se known post winding machines. That is to say, two separate machines are used for button sewing and post winding.

Admittedly there is known a button sewing machine which performs both the above-mentioned operations, but because of its disadvantages it has not found widespread use in the garment industry. Its chief disadvantages are the following: (a) high purchase cost: US 10,750, (b) productivity is only slightly increased due to low rpm (400 rpm) the button is secured to the work 2 or 3 threads only, while the post winding is performed with -14 turns, (d) a special thread must be used, and (e) use and maintenance of the machine is cumbersome and expensive.

This invention aims to provide a machine which performs the button sewing with blind stitching, then after turning the sewn-on button from a button-sewing to a post-winding position, it winds thread round the post, while eliminating the disadvantages of existing machines.

According to the present invention, there is provided a sewing machine for the production in one operational cycle of button sewing with blind stitching and post winding, comprising a main drive shaft, a program control member positively coupled to the main drive shaft, a button clamping and turning device connected by a transmission to the control member for turning the button by at least 75 between a button sewing position and a post winding position, means connected to the control member for effecting the button sewing and post winding, a work-supporting plate connected for reciprocating movement to the control member, the button clamping and turning device being mounted on a button turning shaft journalled on the worksupporting plate, and a work-gripping device which is positively coupled with the button turning shaft in the direction of work movement but which is movable in the directions of work gripping and button turning independently of the button turning shaft.

The invention is described by way of example only with reference to the accompanying drawings, in which FIG. 1 schematically illustrates the kinematic layout of a combined button sewing and post-winding machine according to the invention;

FIG. 2 is a fragmentary view in perspective on an enlarged scale of a portion of the apparatus shown in FIG. 1; and

- FIG. 3 is a fragmentary view in perspective of a portion of the sewing machine of the invention at the location of the button sewing station.

Referring to the drawing, wherein conventional sewing machine parts have been omitted for the sake of clarity, the machine has a main drive shaft 1 for driving the sewing mechanism. The main shaft 1 receives its drive in the usual way from a round belt or a V-belt, not shown. A cranked driving device located at one end of the main shaft 1 provides the usual vertical alternating drive for the needle bar. The lateral swing of the needle bar is controlled by a cam disc 4 through an adjustable lever mechanism.

The machine has a button clamping device 8 which also receives its drive for linear movement in the direction of the main shaft 1 and for button turning between a button sewing and a post winding position from cam disc 4. The cam disc 4 is adapted to be driven from the main shaft 1 via a worm 2 and a worm wheel 3. The cam disc 4 has an internal button turning recess, near the top of the disc 4 as viewed, in which is fitted a roller secured on a one-armed level 5 which transmits its movement according to the shape of the recess to a cranked shaft 7 via a ball-jointed rod 6, so as to turn the device 8 by at least but preferably by a full quartertum. The button clamping device 8 is adjustably secured on the shaft 7. Its adjustment varies the distance between the button and the work (fabric) and thus varies the length of the post. During the lock or finishing stitch of the post-wound button sewing, after the needle has left the work, the button turning recess of the cam disc 4 starts the rotation of the button clamping device 8 which terminates at the next downward needle movement. Meanwhile, the work remains in its position pressed against a gauge plate 92. This is ensured by a work gripping or clamping device 10-12 both in the direction of button turning and work gripping but which is positively coupled to the button clamping device 8 in the direction of work movement, the work gripping device comprising a cammed arm 10 coupled to a compression spring 12 via a roller 11. The end of the arm 10 remote from the gauge plate 9 is secured to a base plate 9a connected with the gauge plate 9, so that the work of the work gripping device is independently movable of the button clamping device 8 in the direction of the work gripping movement of the arm 10 and of the button turning movement of the device 8. However, the base plate 9a, and thus the gauge plate 9 also, are reciprocatable in a direction substantially parallel with the shaft 7 by virtue of a cammed connection with the cam disc 4, as shown in the drawing. The base plate 9a provides journalled supports for the shaft 7.

The sewing on of four-hole buttons without crossthreading and with post winding in accordance with modern requirements necessitates the provision of three mutually independent, lock stitches, for which purpose the machine is provided with per se known control means for thread cutting and thread pulling. After the first stitch has been made, a blade-controlling cam 13 engaging the internal surface of the cam disc 4 lifts a locking lever 15 via a lifting lever 14 and against the force of a spring 16, as a result of which an arm 17 having a roller 32 at its end enters, under the mantle surface of a control drum 19 which is settably secured on the main shaft 1. Under the effect of the rotation of the main shaft 1 and in accordance with the shape of the cam groove 31 in the control drum 19 the roller 32 on arm 17 is displaceable along the longitudinal axis of the machine. As a result, a rod 21 is also displaced owing to its connection to the arm 18 via a two-armed forked lever 20 and moves a blade holder 23 via another forked lever 22.

In the basic position a cam 24 provided on the mantle surface of the control drum 19 lifts the roller 32 of arm 17 out of the groove, while the locking arm is caused by spring 16 to apply against the arm 17 and to lock it after removal from the groove. Thereafter the roller 32 of arm 17 cannot re-enter the groove in the control drum 19 until the blade controlling cam 13 terminates the locking.

The appropriate shaping of the groove in the control drum l9 ensures that the cutting of the thread for a lock stitch takes place in the region of maximum speed of movement of the blade holder 23.

The shaping of the groove 31 in the control drum 19 and the construction of the movement-transmitting parts of the transmission, which is limited on two sides, simultaneously ensure the positive control of the blade holder 23 in both directions. In the basic position a cam 24 provided on the mantle surface of the control drum l9 lifts the roller of arm 17 out of the groove, while the locking arm 15 is caused by spring 16 to apply against the roller arm 17 and to lock it after removal from the groove. Thereafter the roller arm 17 cannot re-enter the groove in the control drum 19 until the blade controlling cam 13 terminates the locking. The withdrawal of the severed thread is controlled by a thread tensioning control claw 25 on the outer surface of the cam disc 4 via a two-armed lever 26 looking a thread tensioner 27 in such a manner that the per se known needle-bar thread drawing mechanism can only pull the span of the thread on the side of the needle after actuation of the thread tensioner 27, since the thread limb on the bobbin side is clamped by the thread tensioner 27.

In the interest of facilitating the adjustability of the usual thread guide 28, known per se in chain-stitch button sewing machines, and of increasing the operational reliability of the machine, the thread guide 28 is constructed in the form of a mechanism which, in addition to its known swinging movement, can also move axially by virtue of the gearing and connection shown schematically in the drawing.

After the stoppage of the machine, a lifting arm 29 raises the roller 11 from the arm 10 of the work gripping device. Thus the arm 10 will rise under the action of a spring 30, whereafter the work can be removed and replaced by fresh work.

As shown in FIG. 2, the machine has a button clamping device 8 which receives its drive both for linear movement in the direction of the main shaft 1 and for button turning between a button sewing and a post winding position from cam disc 4. The cam disc 4 is adapted to be driven from the main shaft 1 via a worm 2 and a worm wheel 3, the latter being mounted on a shaft 33. The cam disc 4 has an internal button turning recess, near the top of the disc 4 as viewed, in which there is fitted a roller secured on a one-armed lever 5 which transmits its movement according to the shape of the recess to a shaft 7 via a ball-jointed rod 6 (FIGS. 1 and 2) or a rack-toothed wheel engagement (FIG. 3) so as to turn the device 8 by at least 75, but preferably by a full quarter-turn. The button clamping device 8 is adjustably secured on the shaft 7. Its adjustment varies the distance between the button and the work (fabric) and thus varies the length of the post.

During the lock or finishing stitch of the post-wound button sewing, after the needle has left the work, the button turning recess of the cam disc 4 startsthe rotation of the button clamping device 8 which terminates at the next downward needle movement. Meanwhile, the work remains in its position pressed against a base plate 92. This is ensured by a work gripping or clamping device comprising a cammed arm 10 coupled to a compression spring 12 via a roller 11. At one end the arm 10 is pivoted to the base plate 9a so that the work gripping device is independently movable of the button clamping device 8 in the direction of the work gripping movement of the arm 10 and also of the button turning movement of the device 8. The base plate 9a is reciprocable in a direction substantially parallel with the shaft 7 by virtue of a cammed connection with the cam disc 4, as shown in the drawing. The base plate provides journalled supports for the shaft 7.

Since the sewing mechanism of the combined post winding and button sewing machine according to the illustrated embodiment of this invention has been constructed on the basis of the known principles of traditional sewing machines, but with these principles refined and developed, it fully eliminates the disadvantage of the known button sewing and post-winding machine.

We claim:

1. A sewing machine for the production in one operational cycle of sewing a button on a work piece including blind stitching and post winding, comprising a main drive shaft, a multi-lobed program controlling disc positively coupled to the main drive shaft, a transmission connected to the main drive shaft, a button clamping and turning device connected to the transmission so as to turn the button by at least between the button sewing position and a post winding position, means connected to the control member for effecting the button sewing and post winding, a work-supporting plate connected to the control member for reciprocating movement, a button turning shaft journalled on the work piece supporting plate and carrying the button clamping and turning device, and a work piecegripping device which is positively coupled with the button turning shaft in the direction of work piece movement but which is movable in the directions of work piece gripping and button turning independently of the button turning shaft.

2. In an arrangement for moving the button and holding down the material of a work piece for sew-on button sewing machines which form a shaft during the sewing on with a blind stitch without a connection stitch, and thereafter turn the button for the purpose of winding the thread around the formed shaft, the sewing of a button and the winding operation taking place in one and the same operating cycle, the machine having a main drive shaft, a multi-lobed programming disc positively coupled to the main drive shaft, a mechanism for advancing the work piece material, means controlling said mechanism by the programming disc, a thread cutting device and thread brake, the improvement which comprises a stitch disc with an arrangement for taking up the button which is provided with a button moving shaft, means with its ends in form of a needle are arranged at the stitch disc, a needle rod carrying frame, the button moving shaft being disposed at the stitch disc on the vertical swivel surface of the needle frame and affixed in the direction of the alternative stitch disc movement but being turnable in the direction of the axis.

3. An arrangement according to claim 2, wherein the programming disc constantly interacts with a button moving shaft via a connection rod, and comprising a roller lever which is connected pivotally to a then following turn at least by 90 of the button moving shaft and provided with a suitable guiding curve.

4. An arrangement according to claim 3, comprising an arm for holding down the material of the work piece at the stitch plate in the direction of its alternating movement, a lever pivotable about an axis parallel to thread cutting mechanism 

1. A sewing machine for the production in one operational cycle of sewing a button on a work piece including blind stitching and post winding, comprising a main drive shaft, a multi-lobed program controlling disc positively coupled to the main drive shaft, a transmission connected to the main drive shaft, a button clamping and turning device connected to the transmission so as to turn the button by at least 75* between the button sewing position and a post winding position, means connected to the control member for effecting the button sewing and post winding, a work-supporting plate connected to the control member for reciprocating movement, a button turning shaft journalled on the work piece supporting plate and carrying the button clamping and turning device, and a work piece-gripping device which is positively coupled with the button turning shaft in the direction of work piece movement but which is movable in the directions of work piece gripping and button turning independently of the button turning shaft.
 2. In an arrangement for moving the button and holding down the material of a work piece for sew-on button sewing machines which form a shaft during the sewing on with a blind stitch without a connection stitch, and thereafter turn the button for the purpose of winding the thread around the formed shaft, the sewing of a button and the winding operation taking place in one and the same operating cycle, the machine having a main drive shaft, a multi-lobed programming disc positively coupled to the main drive shaft, a mechanism for advancing the work piece material, means controlling said mechanism by the programming disc, a thread cutting device and thread brake, the improvement which comprises a stitch disc with an arrangement for taking up the button which is provided with a button moving shaft, means with its ends in form of a needle are arranged at the stitch disc, a needle rod carrying frame, the button moving shaft being disposed at the stitch disc on the vertical swivel surface of the needle frame and affixed in the direction of the alternative stitch disc movement but being turnable in the direction of the axis.
 3. An arrangement according to claim 2, wherein the programming disc constantly interacts with a button moving shaft via a connection rod, and comprising a roller lever which is connected pivotally to a then following turn at least by 90* of the button moving shaft and provided with a suitable guiding curve.
 4. An arrangement according to claim 3, comprising an arm for holding down the material of the work piece at the stitch plate in the direction of its alternating movement, a lever pivotable about an axis parallel to the swivel surface of the needle rod frame, and a tensioned roll for guiding the arm for holding down the material of the work piece.
 5. A sewing machine as claimed in claim 1 comprising a positively controlled cam mechanism for thread cutting after termination of the button sewing but before the post winding.
 6. A sewing machine as claimed in claim 5, comprising a thread tensioning device, and a cammed member for controlling the tensioning device, the cammed member serving to withdraw the thread severed by the thread cutting mechanism. 